使用注解进行开发时,需要在applicationContext.xml中配置组件扫描
<context:component-scan base-package="cn.guixinchn"></context:component-scan>
然后使用注解@Service、@Repository 标识需要Spring实例化的类
使用@Autowired、@Qualifier进行依赖注入
@Repository("userDao")
public class UserDaoImpl implements UserDao {
public void save() {
System.out.println("save running....");
}
}
@Service("userServer")
public class UserServerImpl implements UserServer {
@Autowired
@Qualifier("userDao")
private UserDao userDao;
public UserServerImpl(UserDao userDao) {
this.userDao = userDao;
}
public void save() {
userDao.save();
}
}
使用注解充当配置文件
@Configuration
@ComponentScan("cn.guixinchn")
@PropertySource("classpath:jdbc.properties")
public class SpringConfiguration {
@Value("${jdbc.driver}")
private String driver;
@Value("${jdbc.url}")
private String url;
@Value("${jdbc.username}")
private String username;
@Value("${jdbc.password}")
private String password;
@Bean(name="dataSource")
public DataSource getDataSource () throws PropertyVetoException {
ComboPooledDataSource dataSource = new ComboPooledDataSource();
dataSource.setDriverClass(driver);
dataSource.setJdbcUrl(url);
dataSource.setUser(username);
dataSource.setPassword(password);
return dataSource;
}
}
测试
@Test
public void test4() throws SQLException {
//获取注解配置类的上下文对象
ApplicationContext applicationContext = new AnnotationConfigApplicationContext(SpringConfiguration.class);
//拿到数据源
DataSource dataSource = (DataSource) applicationContext.getBean("dataSource");
//获得连接对象
Connection connection = dataSource.getConnection();
System.out.println(connection);
connection.close();
}
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>5.0.2.RELEASE</version>
</dpendency>
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = SpringConfiguration.class)
public class JunitTest {
@Autowired
private UserServer userServer;
@Test
public void test(){
userServer.save();
}
}
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>5.0.3.RELEASE</version>
</depe
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>5.0.3.RELEASE</version>
</dependency>
public class Student {
private String name;
private int age;
/*省略set个get方法,tostring方法*/
}
<!--Spring容器加载properties文件-->
<context:property-placeholder location="classpath:jdbc.properties"></context:property-placeholder>
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="driverClass" value="{jdbc.driver}"></property>
<property name="jdbcUrl" value="{jdbc.url}"></property>
<property name="user" value="{jdbc.username}"></property>
<property name="password" value="{jdbc.password}"></property>
</bean>
<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource"></property>
</bean>
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class JdbcTemplateTest {
@Autowired
private JdbcTemplate jdbcTemplate;
@Test
public void test1(){
int i = jdbcTemplate.update("insert into student value (?, ?)", "张三", 18);
System.out.println(i);
}
}
JdbcTemplate模板里面通过RowMapper的实现类BeanPropertyRowMapper,为我们封装实体类
@Test
public void queryAllTest(){
List<Student> studentList = jdbcTemplate.query("select * from student", new BeanPropertyRowMapper<Student>(Student.class));
System.out.println(studentList);
}
@Test
public void queryOneTest(){
Student student = jdbcTemplate.queryForObject("select * from student where name = ?", new BeanPropertyRowMapper<Student>(Student.class), "张三");
System.out.println(student);
}
@Test
public void queryCountTest(){
Long num = jdbcTemplate.queryForObject("select count(*) from student", Long.class);
System.out.println(num);
}